The number 72642
72642 is a composite number with 8 divisors. Its prime factorisation is 2 × 3 × 12107. Divisors (8): 1, 2, 3, 6, 12107, 24214, 36321, 72642.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
What is special about 72642: a happy number: repeatedly adding the squares of its digits reaches 1.
- 2
72642 is composite. Its prime factorisation is
- 3
The divisors add up to 145296; without 72642 itself that is 72654, so 72642 is abundant (72654 is more than 72642). Euler's totient φ(72642) = 24212 numbers up to 72642 share no factor with it.
- 4
The digits of 72642 add up to 21, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 156 steps to reach 1.
LaTeX source of the formulas on this page
\[ 72642 = 2 \times 3 \times 12107 \]
72642 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 8 |
| Sum of divisors | 145296 |
| Euler totient φ(n) | 24212 |
| Square | 5276860164 |
| Cube | 383321676033288 |
| Square root | 269.521799 |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 156 |
| Scientific notation | 7.2642 × |
72642 in other forms
| Form | Value |
|---|---|
| In words | seventy-two thousand six hundred and forty-two |
| Binary (base 2) | 10001101111000010 |
| Octal (base 8) | 215702 |
| Hexadecimal (base 16) | 11BC2 |
| Base 3 | 10200122110 |
| As time | 72642 seconds = 20 h 10 min 42 s |
Is 72642 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (72642 ÷ 2 = 36321) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (72642 ÷ 3 = 24214) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 2) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (72642 ÷ 6 = 12107) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 3) | A number is divisible by 7 if double the last digit and subtract it from the rest: the result is a multiple of 7. |
| 8 | No (remainder 2) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 3) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 2) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 9) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 6) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 72642 a prime number?
No. 72642 = 2 × 3 × 12107, so it is divisible by 2.
What are the factors of 72642?
1, 2, 3, 6, 12107, 24214, 36321, 72642.
What is 72642 in binary?
10001101111000010 (hexadecimal 11BC2, octal 215702).
What is the square root of 72642?
About 269.5218.
Is 72642 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 72642?
72642 is a happy number: repeatedly adding the squares of its digits reaches 1.